import 'package:flutter/material.dart';

class JDTextPage extends StatefulWidget {
  JDTextPage({Key key, this.title}) : super(key: key);

  // This widget is the home page of your application. It is stateful, meaning
  // that it has a State object (defined below) that contains fields that affect
  // how it looks.

  // This class is the configuration for the demo.funcation.state. It holds the values (in this
  // case the title) provided by the parent (in this case the App widget) and
  // used by the build method of the State. Fields in a Widget subclass are
  // always marked "final".
  String title;

  @override
  State createState() => _JDTextPageState();
}

class _JDTextPageState extends State<JDTextPage> {
  int _counter = 0;

  void _incrementCounter() {
    setState(() {
      // This call to setState tells the Flutter framework that something has
      // changed in this State, which causes it to rerun the build method below
      // so that the display can reflect the updated values. If we changed
      // _counter without calling setState(), then the build method would not be
      // called again, and so nothing would appear to happen.
      _counter++;
    });
  }

  @override
  void initState() {
    super.initState();
    print("initState");
  }

  @override
  Widget build(BuildContext context) {

    print("build");
    // 在Widget树中向上查找最近的父级`Scaffold` widget
    // Scaffold scaffold = context.ancestorWidgetOfExactType(Scaffold);

    //获取路由参数

    if (widget.title == null) {
      var args = ModalRoute.of(context).settings.arguments;
      Map map = args as Map;
      if (map != null) {
        widget.title = map["title"] as String;
      } else {
        widget.title = "Default Text Page";
      }
    }
    // This method is rerun every time setState is called, for instance as done
    // by the _incrementCounter method above.
    //
    // The Flutter framework has been optimized to make rerunning build methods
    // fast, so that you can just rebuild anything that needs updating rather
    // than having to individually change instances of widgets.
    return Scaffold(
      appBar: AppBar(
        // Here we take the value from the MyHomePage object that was created by
        // the App.build method, and use it to set our appbar title.
        title: Text(widget.title),
      ),
      body: Center(
        // Center is a layout widget. It takes a single child and positions it
        // in the middle of the parent.
        child: Column(
          // Column is also layout widget. It takes a list of children and
          // arranges them vertically. By default, it sizes itself to fit its
          // children horizontally, and tries to be as tall as its parent.
          //
          // Invoke "debug painting" (press "p" in the console, choose the
          // "Toggle Debug Paint" action from the Flutter Inspector in Android
          // Studio, or the "Toggle Debug Paint" command in Visual Studio Code)
          // to see the wireframe for each widget.
          //
          // Column has various properties to control how it sizes itself and
          // how it positions its children. Here we use mainAxisAlignment to
          // center the children vertically; the main axis here is the vertical
          // axis because Columns are vertical (the cross axis would be
          // horizontal).
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            Text("Hello world "* 10,  //字符串重复六次
              textAlign: TextAlign.center,
            ),

            Text("I'm Jack. "* 14,
              maxLines: 1,
              overflow: TextOverflow.ellipsis,
            ),

            //MediaQueryData.textScaleFactor
            Text("Hello world",
              textScaleFactor: 1.5,
            ),

            Text("Hello world",
              style: TextStyle(
                  color: Colors.blue,
                  fontSize: 18.0,
                  height: 1.2,
                  fontFamily: "Courier",
                  background: new Paint()..color=Colors.yellow,
                  decoration:TextDecoration.underline,
                  decorationStyle: TextDecorationStyle.dashed
              )
            ),

            Text.rich(TextSpan(
                children: [
                  TextSpan(
                      text: "Home: "
                  ),
                  TextSpan(
                      text: "https://flutterchina.club",
                      style: TextStyle(
                          color: Colors.blue
                      ),
//                      recognizer: _tapRecognizer
                  ),
                ]
            )),


            DefaultTextStyle(
              //1.设置文本默认样式
              style: TextStyle(
                color:Colors.red,
                fontSize: 20.0,
              ),
              textAlign: TextAlign.start,
              child: Column(
                crossAxisAlignment: CrossAxisAlignment.start,
                children: <Widget>[
                  Text("hello world"),
                  Text("I am Jack"),
                  Text("I am Jack",
                    style: TextStyle(
                        inherit: false, //2.不继承默认样式
                        color: Colors.grey
                    ),
                  ),
                ],
              ),
            ),

            Text(
              'You have pushed the button this many times:',
            ),
            Text(
              '$_counter',
              style: Theme.of(context).textTheme.display1,
            ),
          ],
        ),
      ),
      floatingActionButton: FloatingActionButton(
        onPressed: _incrementCounter,
        tooltip: 'Increment',
        child: Icon(Icons.add),
      ), // This trailing comma makes auto-formatting nicer for build methods.
    );
  }


  /***************** 重写一些方法 *******************/

  @override
  void didUpdateWidget(JDTextPage oldWidget) {
    super.didUpdateWidget(oldWidget);
    print("didUpdateWidget");
  }

  @override
  void deactivate() {
    super.deactivate();
    print("deactive");
  }

  @override
  void dispose() {
    super.dispose();
    print("dispose");
  }

  @override
  void reassemble() {
    super.reassemble();
    print("reassemble");
  }

  @override
  void didChangeDependencies() {
    super.didChangeDependencies();
    print("didChangeDependencies");
  }

}
